Exercise 4 .1. Scientists haven’t done much research to find life forms on other planets. F
2. Earth’s temperate atmosphere makes it accommodative to life forms. T
3. Earth’s distance from the Sun allows it to receive just enough heat. T
4. No other planets have any of Earth’s life-sustaining feature. F
5. Earth is still the only planet with all necessary conditions for life. T
Exercise 5.My cousin, Ron (1.have)…has....a dog. It (2.be)…is…..an intelligent and beautiful pet with a short tail and big brown eyes. Its name (3.be)…is……..Rex and it (4.like)……likes…..eating meat. Although Rex (5.bark)……barks…..when strange guests visit, it (6.never/ bite)…never……..anyone; To be honest, Rex (7.be)…is……..very friendly. It (8.not/ like)…doesn't……..eating fruits, such as apple, orange, banana, or grape, but it (9.often/ play)…often play……..with them. If the weather (become)…becomes……..bad, Rex (10.just/ sleep)…just sleeps……..in his cage all day. Ron (11.play)…plays……..with his dog every day after school. Because there (12.be)…are……..many people on the road, Ron (13.not/ let)……doesn't let…..the dog run into the road. Ron (14.often/ take)…often takes……..Rex to a large field in the park to enjoy the peace there. Rex (15.sometimes/ be)……sometimes is…..naughty, but Ron loves it very much.